Rotary piston internal combustion engine, especially of trochoidal construction

ABSTRACT

A rotary piston internal combustion engine, especially of trochoidal construction which essentially consists of lateral housings and of at least one casing housing, possibly also of one or several intermediate housings, provided with a sealing element between the abutment surface of the housing parts to be connected with each other which surrounds the channels for the cooling and lubricating media; the sealing element which serves the purpose of liquid seal and consists in particular of rubber or synthetic plastic material is thereby surrounded by a second sealing element serving the purpose of gas seal; these two sealing elements may thereby be arranged in only one annular groove or in different annular grooves.

United States Patent 1 Lamm [451 Oct. 29, 1974 [75] Inventor: Heinz Lamm, Esslingen-St.

Bernhardt, Germany [73] Assignee: Daimler-Benz Aktiengesellschaft,

Stuttgart, Germany [22] Filed: Oct. 6, 1972 [21] Appl. No.: 295,692

[30] Foreign Application Priority Data 3,695,790 10/1972 Jones 418/149 3,736,078 5/1973 Read et al.....

FOREIGN PATENTS OR APPLICATIONS 223,876 10/1962 Austria 418/149 Primary ExaminerC. .I. I-Iusar Attorney, Agent, or FirmCraig & Antonelli [5 7] ABSTRACT A rotary piston internal combustion engine, especially of trochoidal construction which essentially consists of lateral housings and of at least one casing housing, possibly also of one or several intermediate housings, provided with a sealing element between the abutment Surface f h h99in r2ar abs cqnnep edwi each other which surrounds the channels for the cooling and lubricating media; the sealing element which serves the purpose of liquid seal and consists in particular of rubber or synthetic plastic material is thereby surrounded by a second sealing element serving the purpose of gas seal; these two sealing elements may thereby be arranged in only one annular groove or in different annular grooves.

14 Claims, 9 Drawing Figures Oct. 7, 1971 Germany 2150007 [52] US. Cl. 418/149 [51] Int. Cl. F01c 19/00 [58] Field of Search 418/60, 149

[56] References Cited UNITED STATES PATENTS 2,702,509 2/1955 Garnier 418/149 3,452,723 7/1969 Keylwert 3,490,383 1/1970 Parrett 3,575,538 4/1971 Berkowitz 418/149 PATENTEuncrzswm 1844394 ROTARY PISTON INTERNAL COMBUSTION ENGINE, ESPECIALLY OF TROCIIOIDAL CONSTRUCTION The present invention relates to a rotary piston internal combustion engine, especially of trochoidal type of construction, essentially consisting of lateral housings and of at least one casing housing, and possibly of one or several intermediate housings, with a respective sealing element arranged between the abutment surfaces of the housing parts to be connected with one another and surrounding the channels for cooling and lubricating media, whereby the sealing elements consist, for example, of rubber.

These sealing elements consisting of rubber and constructed as so-called O-rings have more or less the purpose of providing a liquid seal.

However, since the individual housing parts of a rotary piston internal combustion engine are securely clamped together by tie-rods, since the seal between these housing parts is purely metallic and since an optimum gas seal is therefore not attainable, the sealing elements surrounding the channels receive an additional task; namely, the task that they also must provide a seal with respect to the' gas.

If, however, a hot gas or a hot fuel-air mixture comes into contact with the sealing elements intended as liquid seals, then the latter are destroyed. The consequence thereof is that gas enters the cooling or lubricating circulatory system and a completely satisfactory continuous feed of the cooling or lubricating medium is not longer assured.

Furthermore, the heat transfer of the gas-containing cooling or lubricating medium is smaller sothat by reason of the lacking cooling effect, the housing parts become overheated.

The present invention is concerned with the task to avoid the aforementioned shortcomings by simple means in an advantageous manner.

The underlying problems are solved according to the present invention in that the sealing element serving the purpose of liquid seal is surrounded or enclosed by a second gas-sealing" sealing element.

This series-connected gas sealing sealing element connected in front of the liquid seal protects the sealing element disposed therebehind against excessive temperatures and against gas or fuel-air mixture.

In one advantageous embodiment, the second sealing element which may consist of a metallic material and is springy, may be accommodated according to the present invention together with the first sealing element in only one annular groove.

In order that the metallic sealing element can at the same time also carry off some heat, it should also consist of a good thermal conductor material such as, for example, copper.

However, a sealing element can also be used that consists of combined layers with enclosures or borders as are utilized customarily for cylinder head gaskets.

According to further features, the two sealing elements may be arranged according to the present invention in two separate annular grooves of the same housing part or the first sealing element in an annular groove of the lateral or intermediate housing part and the second sealing element in an annular groove of the casing housing or vice versa.

According to a further embodiment, both the lateral or intermediate housing parts as also the casing housing part may be provided with annular grooves, of which two grooves mutually face and abut against one another and receive each one-half of the sealing element.

Furthermore, according to the present invention the second sealing element may be constructed two-partite whose portion disposed nearest to the gas side is pressed by a second springy portion, disposed at the groove bottom of the annular groove, against the abutment surface of a housing part] v L Accordingly, it is an object of the present invention to provide a rotary piston internal combustion engine, especially of trochoidal construction, which avoids by simple means the aforementioned shortcomings and drawbacks encountered in the prior art.

Another object of the present invention resides in a rotary piston internal combustion engine, especially of trochoidal construction, in which the elastic sealing elements used for sealing the lubricating and cooling media passages are effectively protected against premature destruction as a result of contzictwith hot gases or hot fuel-air mixture. i

A further objectof the present invention resides in a rotary piston internal corn on engine in which a completely satisfactory cont l ious feed of the cooling and lubricating media is assured together with adequate cooling to achieve predetermined design considerations.

Still antoher object of the present invention resides in a rotary piston internal combustion engine of trochoidal construction in wh ich the sealing problem between housing casing and lateral housing parts or intermediate housing parts is effectively solved by simple means to optimize the gas tightness.

These and other objects, features and advantages of the present invention .will becomemore apparent from the following description when taken in connection with the accompanying drawing which shows, for purposes of illustration only, several embodiments in accordance with the present invention, and wherein:

FIG. 1 is a partial cross sectional view through a rotary piston internal combustion engine with two sealing elements which are arranged together in a single annular groove; i i w FIG. 2 is a partial cross-sectional view through a modified embodimentof a rotary piston internal combustion engine provided Qvvithtwo sealing elements which are accommodated intwo annular grooves of a housing part; v

FIG. 3 is a partial cross-sectional view through a further modified embodiment of a rotary piston internal combustion engine withtwo sealing elements of which one sealing elementis arrangedin the casing housing and the other sealing elemeiit ih the adjacent housing part;

FIG. 4 is a partial cross sectional .view through another embodiment of afro tary' piston internal combustion engine provided with two sealing element s of which one sealing element-.js arra ng'ed in the casing housing and the other-sealing element is accommodated in the two mutually adjacent housing parts with one-half thereof in each of these adjacent housing parts;

FIG. 5 is a partial cross-sectional view through still another embodiment of a rotary piston internal combustion engine with two sealing elements in a single annular groove in accordance with the present invention of which one sealing element is constructed twopartite;

FIGS. 6 and 7 arepartial cross-sectional views, similar to FIG. 5, through two further embodiments of a rotary piston internal combustion engine with two sealing elements accommodated in a single annular groove of which one sealing element is constructed two-partite;

FIG. 8 is a schematic sectional partial view taken along section line VIIIVIII of FIG. 9, and showing the relative position of the coolant and lubricating channels with respect to the remaining engine structure; and

FIG. 9 is a schematic partial sectional view taken along line IXIX of FIG. 8.

Referring now to the drawing wherein like reference numerals are used throughout the various views to designate like parts, FIGS. 1-7 illustrate respectively a partial cross-sectional view of a lateral housing 1 and of a casing housing 2 of a rotary piston internal combustion engine of otherwise conventional construction, whereby the lateral housings and/or the casing housing are provided with annular-grooves arranged in mutually different manners, in which differently constructed sealing elements of differing materials are embedded. A place respectively designated by reference numeral 3 represents in each of the views the gas side and a place designated by reference numeral 4 the channel side for cooling or lubricating media.

FIGS. 8 and 9 schematically depict the position of the channels 4 for the coolant or lubricant media with respect to the remaining conventional engine structure with a piston P eccentrically rotatable inside of the lateral housing 1 and casing housing 2. In these FIGS. 8 and 9, reference numerals corresponding to those used in conjunction with the remaining FIGS. 1 to 7 are used to depict corresponding features. Reference numerals 6' and 7 indicate the respective orientation of the seals 6 and 7 with respect to one another.

In the casing housing part 2 according to FIG. 1, there is provided a rectangularly shaped annular groove 5-as viewed in cross sectionwhich is intended for the accommodation of a gas sealing" sealing element 6 and of a liquid-sealing sealing element 7. The sealing element 6 disposed on the gas side consists of a metallic material, for example, of copper and is constructed squareas viewed in cross section; the sealing element 7 arranged on the channel side is constructed as so-called O-ring and consists of rubber or synthetic plastic material.

According to FIG. 2, two separate annular grooves 8 and 9 are arranged in the casing housing part 2, of which the annular groove 8 accommodates the sealing element 6 and the annular groove 9 the sealing element 7.

In FIG. 3, both the casing housing 2 as also the lateral housing 1 is provided with one respective annular groove 10 and 11 each. Also in this embodiment, the sealing elements 6 and 7 are arranged in the same sequence and in a similar manner as in FIGS. 1 and 2.

FIG. 4 illustrates an arrangement in which a sealing element 12 is disposed with one half in an annular groove 13 of the casing housing 2 and with another half in an annular groove 14 of the lateral housing 1. The form of this sealing element is circular-as viewed in cross section. The liquid-seal sealing element 7 is accommodated in the annular groove 10 of the casing housing 2.

In the annular groove 5 of the casing housing 2 illustrated in FIG. 5, there is supported, in addition to the sealing element 7 constructed as so-called O-ring, a two-partite sealing element whose two parts are designated by reference numerals 15 and 16. The metallic part 15 has a rectangular cross section whereas the springy or elastic part 16 has a circular cross section.

The part 15 is replaced in FIG. 6 by a U-shaped part 17 partially surrounding the part 16.

According to FIG. 7, a C-shaped part l8as viewed in cross section-is disposed on the inside of the part 17 of the two-partitesealing element, which consists of an open casing 19 with inserted hose spring 20.

The parts 16 and 18 disposed on the groove bottom 21 of the annular groove 5 press their respectively coordinated part 15 or l7 against the abutment surface 22 of the lateral housing 21.

The arrangement in the annular groove 5 taken according to FIG. 7 can be simplified in that the part 17 is omitted, and the part 18 is correspondingly enlarged in such a manner that the part 18 acts directly against the abutment surface 22. However, high thermal loads would, in that case, load and stress the seal excessively.

The sealing elements arranged in the annular grooves may also be constructed different as to shape and size thereof without departing from the spirit of the present invention.

While I have shown and described several embodiments in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to those skilled in the art. and I therefore do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.

What I claim is:

l. A rotary piston internal combustion engine which includes lateral housing means and at least one casing housing means having abutment surfaces, and sealing means arranged between the abutment surfaces of the housing means to be connected with one another, said sealing means being disposed in an annular groove and surrounding channels for cooling and lubricating media, characterized in that a first sealing means serving the purpose of liquid-seal is enclosed by a second sealing means providing a gas seal.

2. A rotary piston internal combustion engine according to claim 1, characterized in that the first sealing means is constituted by a sealing element consisting of rubber or synthetic plastic material.

3. A rotary piston internal combustion engine according to claim 1, characterized in that the engine includes intermediate housing means provided with abutment surfaces, and that first and second sealing means are also provided between abutment surfaces of the intermediate housing means and of respective abutment surfaces of next adjacent other housing means.

4. A rotary piston internal combustion engine according to claim 1, characterized in that the engine is of trochoidal construction.

5. A rotary piston internal combustion engine according to claim 1, characterized in that the second sealing means which consists of a metallic material and is springy, is accommodated together with the first sealing means in only a single annular groove.

6. A rotary piston internal combustion engine according to claim 5, characterized in that the first sealing means is constituted by a sealing element consisting of rubber or synthetic plastic material.

7. A rotary piston internal combustion engine according to claim 1, wherein said engine includes a gas side at one side of the second sealing means, characterized in that the second sealing means is constructed two partite whose part disposed closest to the gas side is pressed by a springy part arranged at the groove bottom of the annular groove against the abutment surface of one of the two parts consisting of lateral housing means and intermediate housing means.

8. A rotary piston internal combustion engine according to claim 7, characterized in that the part on the gas side is constructed rectangularly shaped.

9. A rotary piston internal combustion engine according to claim 8, characterized in that the springy part is circularly shaped--as viewed in cross section.

10. A rotary piston internal combustion engine according to claim 8, characterized in that the springy part is C-shapedas viewed in cross section.

11. A rotary piston internal combustion engine according to claim 7, characterized in that the part on the gas side is U-shaped.

12. A rotary piston internal combustion engine according to claim 11, characterized in that the springy part is circularlyas viewed in cross section.

13. A rotary piston internal combustion engine according to claim 11, characterized in that the springy part is C-shaped-as viewed in cross section.

14. A rotary piston internal combustion engine according to claim 7, characterized in that the first sealing means is constituted by a sealing element consisting of rubber or synthetic plastic material. 

1. A rotary piston internal combustion engine which includes lateral housing means and at least one casing housing means having abutment surfaces, and sealing means arranged between the abutment surfaces of the housing means to be connected with one another, said sealing means being disposed in an annular groove and surrounding channels for cooling and lubricating media, characterized in that a first sealing means serving the purpose of liquid-seal is enclosed by a second sealing means providing a gas seal.
 2. A rotary piston internal combustion engine according to claim 1, characterized in that the first sealing means is constituted by a sealing element consisting of rubber or synthetic plastic material.
 3. A rotary piston internal combustion engine according to claim 1, characterized in that the engine includes intermediate housing means provided with abutment surfaces, and that first and second sealing means are also provided between abutment surfaces of the intermediate housing means and of respective abutment surfaces of next adjacent other housing means.
 4. A rotary piston internal combustion engine according to claim 1, characterized in that the engine is of trochoidal construction.
 5. A rotary piston internal combustion engine according to claim 1, characterized in that the second sealing means which consists of a metallic material and is springy, is accommodated together with the first sealing means in only a single annular groove.
 6. A rotary piston internal combustion engine according to claim 5, characterized in that the first sealing means is constituted by a sealing element consisting of rubber or synthetic plastic material.
 7. A rotary piston internal combustion engine according to claim 1, wherein said engine includes a gas side at one side of the second sealing means, characterized in that the second sealing means is constructed two partite whose part disposed closest to the gas side is pressed by a springy part arranged at the groove bottom of the annular groove against the abutment surface of one of the two parts consisting of lateral housing means and intermediate housing means.
 8. A rotary piston internal combustion engine according to claim 7, characterized in that the part on the gas side is constructed rectangularly shaped.
 9. A rotary piston internal combustion engine according to claim 8, characterized in that the springy part is circularly shaped-as viewed in cross section.
 10. A rotary piston internal combustion engine according to claim 8, characterized in that the springy part is C-shaped-as viewed in cross section.
 11. A rotary piston internal combustion engine according to claim 7, characterized in that the part on the gas side is U-shaped.
 12. A rotary piston internal combustion engine according to claim 11, characterized in that the springy part is circularly-as viewed in cross section.
 13. A rotary piston intErnal combustion engine according to claim 11, characterized in that the springy part is C-shaped-as viewed in cross section.
 14. A rotary piston internal combustion engine according to claim 7, characterized in that the first sealing means is constituted by a sealing element consisting of rubber or synthetic plastic material. 